Question PC won't POST after randomly shutting down ?

Sep 13, 2022
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So I've been stumped for the past week on repairing my pc. How it happened was one day I was programming and my mouse kept cutting in and out so I kept replugging it then it suddenly crashed my pc. After that it would no longer posts and I tried all day refitting components and I even got to the point where I replugged every wire on the mobo and replugged every psu wire to the components. It didnt work so i got upset and put my pc in a box and didnt touch it for three days. During the fourth day I got curious about it and decided to plug it back in. Magically it worked and posted to the login screen of Windows 10. I was extremely happy and decided to put the pc back to where its location originally was. However doing this caused it to no longer post again. I have since then replaced the psu to no avail, I tried resetting cmos and refitting components again and nothing is working. I feel the mobo may be going bad but the ez debug light is on for the cpu and the led lights on the mobo work fine. I refitted the ram sticks and they dont seem to be the culprit. I'm out of ideas, any suggestions?

Parts:
CPU-Ryzen 5 5600X
GPU-Rx580
Ram-2x 8GB DDR4 Vengeance Sticks
Testing PSU-SMART 700w
Old PSU-EVGA 600w
Motherboard-MSI MPG B550 Gaming Plus

Edit:I know the mouse is of concern I have replaced it, i feel the mouse may have damaged the USB 3.0 ports and shorted something. However it doesnt explain why it turned on after 3 days and worked perfectly fine until I turned off again. And it's obvious the motherboard may need replacing but honestly I'm trying to cut costs so I dont really wanna go that route. Just looking for alternatives that may help me.
 
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Aeacus

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I'm trying to cut costs

This is obvious, especially due to this:
PSU-SMART 700w(new psu I just purchased)

You can cheap out on every other component inside the PC except PSU. Since PSU powers everything, it is the most important component inside the PC. Also, while the PSU warranty covers the PSU itself and you can RMA the blown PSU, the PSU warranty doesn't cover any other component the PSU fried.

Most people learn the hard way not to cheap out on a PSU when low quality PSU blows and takes part of the system or the whole system with it. Even entire houses have been burned down because of the fire low quality PSU caused when it blowed up,
news article: https://www.thesundaily.my/archive/...wer-supply-unit-computer-updated-LTARCH461974

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Now, what might have happened to your PC, is that your old PSU went sky high and fried something else as well. Hence why even PSU replacement (if you can call it at that, since Smart series (Thermaltake?) is junk), doesn't help.

What make and model was your previous PSU?
And what make is your current PSU? I know that Thermaltake has Smart series, but "Smart" can be any brand.

At current moment, you can consider that everything that was connected to PSU, is dead. <- This is the price you pay when you cheap out on PSU.
Here, without 2nd compatible PC, where to test out all your components individually, there is no other way to "fix" your PC.
 
Sep 13, 2022
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You can cheap out on every other component inside the PC except PSU.
Yes, my old PSU was an EVGA 600W. It worked quite well for a long time. I dont think it was the PSU that was faulty. I believe it was my faulty mouse that tripped the circuit and managed to short out something along the lines. It's not the PSU that is the problem, I can confirm this because my EVGA and this Thermaltake PSU function properly on other devices. I know it's a motherboard issue but as I explained above money is tight and I dont want to spend another $200-300 on a new motherboard. I'm just looking for hope here.

Edit: I forgot to mention that I checked the USB 3.0 ports and it was still functioning, keyboard led, and mouse led lights up just no POST.
Hence why even PSU replacement (if you can call it at that, since Smart series (Thermaltake?) is junk), doesn't help.
True, the Thermaltake PSU wasnt meant to be a replacement(my fault on the wording) it was just a placeholder to confirm my suspicions on the PSU being the culprit.
At current moment, you can consider that everything that was connected to PSU, is dead.
God I'd hope not, so far I can confirm the GPU, CPU, HDD, and RAM works properly it's clearly a mobo issue. I must admit I'm trying to cling on to hope as I stated above the PC booted normally after I left it in a plastic container unplugged for 3 days.
This is the price you pay when you cheap out on PSU.
Next time I wont, do you have any suggestions on a proper PSU for my rig that wont break the piggy bank?
 
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Aeacus

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Yes, my old PSU was an EVGA 600W.

What model? Since there is plethora of different model EVGA 600W units out there.

It's like i'm asking what car your have, and all you say is Ford with 4WD. That doesn't tell much.

I dont think it was the PSU that was faulty. I believe it was my faulty mouse that tripped the circuit and managed to short out something along the lines.

Mice use 5V through USB. If there is some short circuit within the mouse itself, it's PSU's job to catch it and safely shut down the PC. Now, if PSU is old or low quality (or both), PSU may not catch the sort circuit in time, letting it to fry other components. Since MoBo is along the way, it can go "pop". And this is most likely what happened.

I know it's a motherboard issue but as I explained above money is tight and I dont want to spend another $200-300 on a new motherboard. I'm just looking for hope here.
God I'd hope not, so far I can confirm the GPU, CPU, HDD, and RAM works properly

How exactly are you confirming that your CPU and RAM are working properly? :unsure:

If you want hope, a checklist to do,
link: https://forums.tomshardware.com/thr...deo-output-troubleshooting-checklist.1285536/

as I stated above the PC booted normally after I left it in a plastic container unplugged for 3 days.

Properly working PSU doesn't need any "cool down" period. It must work at all times, as soon as you press the power button.

Faulty PSU, in the other hand, may work, after most of it's capacitors are drained. Though, main capacitors in PSU (the biggest ones), drain very slowly, taking months or even years to completely drain, when PSU isn't connected to electricity grid.

do you have any suggestions on a proper PSU for my rig that wont break the piggy bank?

Good quality PSU to go for, are Seasonic Focus series or Corsair RM/ RMx/ RMi series.
(All 3 of my PCs are also powered by Seasonic, full specs with pics in my sig.)

Now, if Seasonic Focus or Corsair RM/ RMx/ RMi series look expensive to you, then you better take a look what Seasonic PRIME series and Corsair HX/ HXi /AX /AXi cost, since those are top of the line, regarding PSUs.
(Two of my PCs are powered by Seasonic PRIME, while 3rd is powered by Seasonic Focus.)

Bottom line is, if you want to buy cheap and good PSU, you have to buy two PSUs: the cheap one and the good one.
You already have cheap one, two to be exact. Would 3rd one also be cheap one? :unsure:
 
Sep 13, 2022
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What model? Since there is plethora of different model EVGA 600W units out there.

It's like i'm asking what car your have, and all you say is Ford with 4WD. That doesn't tell much.
It was the EVAG 600W 80 plus series

How exactly are you confirming that your CPU and RAM are working properly? :unsure:
Tested it on my friends rig who also has an AM4 socket MB
Faulty PSU, in the other hand, may work, after most of it's capacitors are drained. Though, main capacitors in PSU (the biggest ones), drain very slowly, taking months or even years to completely drain, when PSU isn't connected to electricity
Yes I feel as if that is the case because last night I retested the EVGA PSU on my friends rig and it wouldnt turn on anymore. So we can just confirm the PSU caused my motherboard to dry? And as you stated below.
Mice use 5V through USB. If there is some short circuit within the mouse itself, it's PSU's job to catch it and safely shut down the PC. Now, if PSU is old or low quality (or both), PSU may not catch the sort circuit in time, letting it to fry other components. Since MoBo is along the way, it can go "pop". And this is most likely what happened.
This was my assumption, I totally agree it's my cheap spending that led to the destruction of my motherboard, I was just suprised why it started working after a few days(I'm not so technical in electrical issues) so I was mainly caught by surprise wondering if there was any hope for me... On the other hand I'm about to reassemble my PC and turn it on and if I get a signal I'll report it to you for further analysis. Thank you.
Good quality PSU to go for, are Seasonic Focus series or Corsair RM/ RMx/ RMi series.
Also I'll definitely look into these as well, thanks.
 
Sep 13, 2022
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Tried the pc on another wallsocket again? If using a "surge protector" of some sort take it out of the equasion.
Hi, and yes it worked to no avail, tried it in multiple surges and wallsocket. For reference when I powered it on the fourth day it was plugged into a surge protector in the same slot its always been plugged into. Thank you.
 

Aeacus

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It was the EVAG 600W 80 plus series

Well, how about PSU part number? Since that tells exactly what PSU you have.

But i think, what you have, is W1 series,
specs: https://www.evga.com/products/product.aspx?pn=100-W1-0600-K1

If so, this is really bottom of the barrel what EVGA has put out. 1st seeing release in 2014 and having only 3 years of warranty.
For good quality PSU, which is reliable, you'd want 7-10 years of warranty for the unit. While when you go with Seasonic PRIME series (any efficiency), then you get 12 years of warranty. <- Only PSU series, in whole world, that offers 12 years of warranty. Oh, Seasonic Focus and Corsair RMx have 10 years of warranty.

Tested it on my friends rig who also has an AM4 socket MB

Okay, this, at least, helps you to narrow down what survived and what didn't.

So we can just confirm the PSU caused my motherboard to dry? And as you stated below.

Yes, this is the most likely cause. Especially since you're using cheap and old PSU, way past it's "due time" (out of warranty).

I was just suprised why it started working after a few days(I'm not so technical in electrical issues) so I was mainly caught by surprise wondering if there was any hope for me...

It is really hard to tell, as of why your PC worked for a while, since when PSU and/or MoBo go "pop", they won't magically fix themselves. PC hardware is inert. Now, if PC hardware would be organic based and "alive", thus "healing" itself, then it would be a different story.

Now, you might get some life into your PC, with fans spinning and lights shining, but if you won't get any signal to monitor, then it doesn't matter if your PC shows signs of life. Something is still toast in your PC.

At this point, i suggest looking towards new MoBo and PSU. Since hooking up new hardware, to old and iffy PSU, most likely will kill the new hardware as well.

Sure, new MoBo and PSU aren't cheap, but you can look all of it as a life's tax. ;)
 
Sep 13, 2022
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Well, how about PSU part number? Since that tells exactly what PSU you have.

But i think, what you have, is W1 series,
Yes that is correct, wow I really should have done research before I bought it. Thank you for the knowledge.
Now, you might get some life into your PC, with fans spinning and lights shining, but if you won't get any signal to monitor, then it doesn't matter if your PC shows signs of life. Something is still toast in your PC.
Yeah its toast now, I've kept it in the plastic container again and it didnt turn on again. I've replicated everything I did. I do remember that the first time it loaded up I was holding up my GPU with some force into the PCIe slot. Could it be that maybe my PCIe slot is dirty or fried? I know that it could still POST with integrated graphics but I'm not sure if my mobo has any. Also the CPU Debug light wasnt on at that time until now.
 

Vic 40

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I do remember that the first time it loaded up I was holding up my GPU with some force into the PCIe slot. Could it be that maybe my PCIe slot is dirty or fried?
No integrated gpu, but can you test with another gpu? Maybe from a friend ....
Your motherboard also has a second pciex16 slot so you could try that as well.

Might still be a motherboard that needs to be replaced, but these are things you still can check.
 

Aeacus

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I know that it could still POST with integrated graphics but I'm not sure if my mobo has any.

Long past are the times when MoBo chipset carried iGPU (integrated GPU). Nowadays, it all depends on a CPU.
To tell a diff, AMD CPUs, with G-suffix, have iGPU (e.g R5 5600G).
On Intel side, it's vice-versa. CPUs with F-suffix, doesn't have iGPU (e.g i5-10400 has iGPU, i5-10400F does not).

Also the CPU Debug light wasnt on at that time until now.

That debug LED doesn't say that CPU is toast. What it does tell, is that MoBo, for whatever reason, is unable to access and utilize the CPU.